Tobacco composition and method of minimizing the irritating properties of tobacco



United States Patent TOBACCO COMPOSITION AND METHOD F MINIMIZING THEIRRITATING PROPER- TlES OF TQBACCO Herman A. Slielanski, Philadelphia,Pa., assignor to Generai Aniline & Film Corporation, New York, N. Y., acorporation of Delaware No Drawing. Application June 20, 1952, SerialNo. 294,715

6 Claims. (Cl. 131-40) This invention relates to a method of minimizingcertain undesirable effects of tobacco and to improved tobacco productsand method of producing the same.

It is generally recognized that part of the irritating properties oftobacco are due to resins and tars present in the tobacco or formedduring the burning thereof.

I have found that poly N-vinyl pyrrolidone, hereinafter generallyreferred to as polyvinyl pyrrolidone, a water soluble polymer describedin U. S. Patent No. 2,265,450, issued December 9, 1941, and obtainableby polymerization of N-vinyl-a-pyrrolidone, has the property ofcombining with tars and resins present in tobacco and materiallyminimizing many irritating effects of the tobacco, in the case ofchewing tobacco and snuif minimizing the irritating effects of thetobacco itself and in the case of smoking tobaccos (cigars, cigarettesand pipe tobaccos) minimizing the amounts of tars and resins or thermaldecomposition or combustion products thereof contained in the smoke.

In the case of tobaccos intended for smoking, I have found that bypassing the smoke through a filter containing polyvinyl pyrrolidone,either the polymer, itself, insolubilized gels of the polymer (of thetype described in copending application of Calvin E. Schildknecht,Serial No. 214,012, now matured as U. S. Patent No. 2,658,045, issuedNovember 3, 1953, obtained by treating a solution of polyvinylpyrrolidone with any inorganic persulfate) or a filter medium comprisinga porous material such as paper or cotton fibers, impregnated or coatedwith polyvinyl pyrrolidone, a substantial amount of resins or tarspresent in the smoke are absorbed so that the amount thereof in smokecoming from the filter is substantially decreased.

1 have also found that by applying a small amount of polyvinylpyrrolidone to tobacco, either in the leaf at any stage of itsprocessing before or after it is ground or cut, polyvinyl pyrrolidoneappears to combine with the resins and tars present therein so that inthe case of chewing tobacco and snufi the irritating properties of thetobacco are substantially minimized and in the case of tobacco intendedfor smoking in pipes, cigarettes or cigars, the amount of tars andresins and also nicotine in the smoke from tobacco containing a smallamount of polyvinyl pyrrolidone, the irritational properties of thesmoke are substantially minimized.

The polyvinyl pyrrolidone may advantageously be incorporated in thetobacco by spraying an aqueous solution of polyvinyl pyrrolidone on thetobacco, either in the leaf or after it has been cut.

Example I A cut smoking tobacco was sprayed with ten per cent aqueoussolution of polyvinyl pyrrolidone having a Fikentscher K value (asdetermined with a 1% aqueous solution of the polymer) of about 25, (100cc. of spray solution being used per pound of tobacco). The tobacco wasthen allowed to dry. A portion of the treated tobacco was rolled intocigarettes. On smoking these cig- 2,737,959 Patented May 10, 1955 icearettes, and also on smoking a portion of the treated tobacco in a pipe,no eflfect on the taste and burning qualities of the tobacco wasnoticed. Cigarettes made from the thus treated tobacco were also smokedin a cigarette smoking machine and a portion of the thus treated tobaccowas smoked in a pipe smoking machine; in both cases it was found thatthe amount of resins and tars in smoke of the treated tobacco wassubstantially less than that from the smoke of the same tobacco whichhad not been treated with polyvinyl pyrrolidone. At the same time thepresence of the polyvinyl pyrrolidone did not appear to exert anyinfluence on the burning properties of the tobacco.

Example 11 400 grams of tobacco, obtained by opening commercialcigarettes, were divided into four IOO-gram batches. One, two, and fourgrams of dry, finely powdered polyvinyl pyrrolidone, having a K value ofabout 30, were thoroughly mixed with three of these batches,respectively. Each batch was then remade into cigarettes and the remadecigarettes smoked.

Example III Commercial cigarette tobacco was remade into cigaretteshaving a hollow tip. Powdered polyvinyl pyrrolidone was placed in thishollow and held in place with a tiny piece of cotton. In certain of thecigarettes mg. of polyvinyl pyrrolidone per cigarette was added, whilein others mg. per cigarette was added and in still others, mg. percigarette was added. These cigarettes were then smoked.

Example IV One, two and four-gram quantities of polyvinyl pyrrolidone inthe form of a ten per cent solution in isopropyl alcohol were sprayedupon three lOO-gram batches of cigarettes, respectively. The tobacco wasair-dried, leaving a fine film of polyvinyl pyrrolidone over thetobacco. The drying was effected with care in a moist atmosphere so thatthere was a minimum loss of the natural moisture of the tobacco. Thethus treated batches of tobacco were remade into cigarettes along with afourth batch of untreated tobacco of the same source. The thus obtainedcigarettes were then compared by smoking.

All the cigarettes obtained in Examples II and 1V which had been treatedwith polyvinyl pyrrolidone or which contained polyvinyl pyrrolidonefilter were considerably milder than the cigarettes made from untreatedtobacco of the same source, those obtained by the method of Examples IIand IV, being superior to those obtained by the method of Example IIIand those obtained by the method of Example IV being superior to thoseof Example II.

in comparing the cigarettes obtained by the methods of Examples 11 andIV, it was found that those containing two per cent polyvinylpyrrolidone were significantly improved over those containing one percent polyvinyl pyrrolidone. The use of the higher four per centpolyvinyl pyrrolidone, particularly in the cigarettes obtained by themethod of Example IV, does not appear to be necessary since there was noincrease in effectiveness at this level.

It will be understood that the foregoing examples are illustrative ofthe present invention and that various modifications may be madetherein.

Due to the relatively high cost of polyvinyl pyrrolidone, it isgenerally preferable to employ the minimum amount thereof which isnecessary to effect the desired decrease in irritational properties ofthe tobacco or the smoke therefrom. Such amount may vary with varioustypes of tobacco and with the method in which the polyvinyl pyrrolidoneis incorporated in the tobacco. The optimum amount can, however, bedetermined by preliminary tests.

It will also be understood that the polyvinyl pyrrolidone may be addedto the tobacco at any stage of its processing,

either before, during or after curing, and advantageously may be addedalong with other common additives to tobacco, such as humectants(glycerine or glycol), flavoring materials, or chlorophyll and itsderivatives especially chlorophyllin (i. e., water soluble chlorophyllfactors). By incorporating the polyvinyl pyrrolidone with tobacco alongwith some other usual additive, the processing is reduced to a minimum.

It also appears that the degree of polymerization of the polyvinylpyrrolidone does not substantially aflect its ability to combine withtars and resins in tobacco and minimize the amount thereof in smoke fromthe tobacco. It is contemplated that water soluble polymers of polyvinylpyrrolidone generally may be used in practicing the present invention(i. e., polymers having a degree of polymerization evidenced byFikentscher K value of 10 to 90). While polyvinyl pyrrolidone having a Kvalue above 90 still combines with the tars and resins in tobacco, suchhigh polymers are somewhat difiicultly soluble, and there fore are notso conveniently applied to tobacco in practicing the invention.Polyvinyl pyrrolidone having a molecular weight within the range ofabout 5,000 to 40,000 with an average molecular weight of about 25,000and a K value of about 30 has been used substantially as a blood plasmasubstitutev Polymers of this type may be used in practicing the presentinvention. However, it appears that batches of polymers having a loweror higher K value than that suitable for certain pharmaceuticalapplications are equally effective for use in accordance with thisinvention and such low or high polymerization may therefore be used, ifdesired.

I claim: 1. Tobacco containing a minor amount of polyvinyl pyrrolidone.

2. The method of minimizing the irritating properties of tobacco smokewhich comprises contacting such smoke with polymeric N-vinylpyrrolidone.

3. A cigarette wherein the tobacco contains a minor amount ofpolyvinylpyrrolidone.

4. A cigar wherein the tobacco contains a minor amount ofpolyvinylpyrrolidone.

5. In a cigarette having a filter, the improvement in the filter whichcomprises the presence therein of an effective amount ofpolyvinylpyrrolidone.

6. A filter for tobacco smoke, said filter containing an etfectiveamount of polyvinylpyrrolidone.

References Cited in the file of this patent UNITED STATES PATENTS160,138 Appleby Feb. 23, 1875 1,507,925 Marshall Sept. 9, 1924 FOREIGNPATENTS 11,419 Great Britain 1902 680,788 Great Britain Oct. 8, 1952OTHER REFERENCES Products Pharmaceutiques, vol. 4, No. 9, pages 397 to403, inclusive.

Products Pharmaceutiques, vol. 4, No. 8, Aug. 1949, pages 350-356.

1. TOBACCO CONTAINING A MINOR AMOUNT OF POLYVINYL PYRROLIDONE.